feat: auto-register skills from registry on arctl configure #395
Description
Today, arctl configure <client> wires up the MCP server endpoint to a user's editor (Cursor, VS Code, Claude Code), but does not install any skills. As a result, Claude has no awareness of what skills exist in the registry and cannot self-discover or pull them during a task. This issue proposes extending arctl configure to also install a dedicated registry skill — a skill that teaches Claude how to discover and pull other skills, search through the registry, deploy items etc., on demand.